Necrosis (in Greek Νεκρός = "dead") is the name given to unnatural death of cells and living tissue. It begins with cell swelling, chromatin digestion, and disruption of the plasma membrane and organelle membranes. Late necrosis is characterized by extensive DNA hydrolysis, vacuolation of the endoplasmic reticulum, organelle breakdown, and cell lysis. The release of intracellular content after plasma membrane rupture is the cause of inflammation in necrosis.
In contrast to apoptosis, cleanup of cell debris by phagocytes of the immune system is generally more difficult, as the disorderly death generally does not send cell signals which tell nearby phagocytes to engulf the dying cell. This lack of signaling makes it harder for the immune system to locate and recycle dead cells which have died through necrosis than if the cell had undergone apoptosis.
Several species of spiders possess toxins proven to cause necrosis:
Spiders suspected of, but not shown to cause necrosis:
The standard therapy of necrosis (wounds, bedsores, burns etc.) is surgical debridement of necrotic tissue. Another option for removal of necrotic tissue would be use of an enzymatic debriding.
In selected cases special maggot therapy has been utilized with good results.
Publication No. WO/2009/143429 Published on Nov. 26, Assigned to Baxter International, Baxter Healthcare S.a. for Vegf165 Delivered By Fibrin Sealant To Reduce Tissue Necrosis (Austrian, American Inventors)
Nov 30, 2009; GENEVA, Dec. 1 -- Rainer Mittermayr and Heinz Redl, both of Austria and and Sam L. Helgerson, United States of America, have...